Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

MATLAB symbolic function shouldn't be symbolic

  1. Oct 29, 2008 #1

    I am getting this error when I try to run the code (at bottom):

    check =


    ??? Undefined function or method 'gt' for input arguments of
    type 'sym'.

    Error in ==> hw at 15
    if check > 10

    The value "check" seems to be a real value, not symbolic. It outputs a value of 1 in the terminal. Can anyone help me resolve this problem?


    clear all
    syms z p x;
    z = -10;
    p = 0;
    while p <20
    while z < 20
    G1 = tf([1 z],[1 p]);
    X1 = (x+z)/(x+p);
    G2 = tf([1],[1 2.5 1]);
    X2 = (1/(x^2+2.5*x+1));
    TF = G1*G2/(1+G1*G2);
    XF = X1*X2/(1+X1*X2);
    z = z + .1;
    check = limit(XF,x,0)
    if check > 10

    [Wn,Z] = damp(TF)

    p = p+.1;
    Last edited: Oct 29, 2008
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted